Image recording system and image recording apparatus

ABSTRACT

A transmitting apparatus transmits encrypted image data created by encrypting image data by using an authentication code as an encryption key and the first converted information created by digesting the authentication code by using a one-way function to an image recording apparatus. The image recording apparatus creates the second converted information by digesting an authentication code received directly from the user by using a one-way function, decrypts the received encrypted image data into image data by using the received authentication code as a decryption key if the created second converted information and the received first converted information coincide, and creates and records an image based on the decrypted image data.

This application is the national phase under 35 U.S.C. §371 of PCTInternational Application No. PCT/JP2004/005102 which has anInternational filing date of Apr. 8, 2004 and designated the UnitedStates of America.

TECHNICAL FIELD

The present invention relates to an image recording system that collatesinformation received by an image recording apparatus with informationreceived from a user and records an image if these pieces of informationcorrespond to each other, and relates to the image recording apparatus.

BACKGROUND ART

A method for recording an image with an image recording apparatusfunctioning as a printing apparatus is in transition from a conventionalmethod in which an image is recorded with an image recording apparatusconnected to a transmitting apparatus for transmitting informationthrough a cable, such as a personal computer (PC), to a method in whichthe image recording apparatus and the transmitting apparatus areconnected to a communication network, image data is transmitted from thetransmitting apparatus to the image recording apparatus through thecommunication network, and the image recording apparatus outputs animage. In such an environment, recorded matters produced by recordingimages on sheets according to instructions from a plurality of users aremixed in a storing unit for recorded matters, and there is a possibilitythat a recorded matter may be taken away by other user. The informationhandled by the image recording apparatus may contain confidentialinformation, such as documents describing a corporate secret, and it isdifficult to maintain the confidentiality of information handled by theimage recording apparatus under a condition in which many unspecifiedpeople can take away recorded matters.

Therefore, there was developed an image recording apparatus that storesimage data without recording an image when the image recording apparatusreceives the image data transmitted from a transmitting apparatus, andrecords the image after the user directly operates the image recordingapparatus and inputs a record instruction. Japanese Patent ApplicationLaid-Open No. 3-269756 (1991) discloses a technique in which a personalidentification number is transmitted together with image data from atransmitting apparatus to an image recording apparatus, and the imagerecording apparatus comprises means that is directly operated by a userfor inputting a personal identification number, and records an imageafter receiving an input of the same personal identification number andverifying the user. Moreover, in order to prevent image data flowing ona communication network or image data stored in an image recordingapparatus from being read, Japanese Patent Application Laid-Open No.6-124178 (1994) discloses a technique in which a transmitting apparatustransmits encrypted image data and a key code to an image recordingapparatus, and the image recording apparatus stores encrypted image datain advance and records an image by decrypting the image data by usingthe key code when it receives a correct password.

Since the technique disclosed in Japanese Patent Application Laid-OpenNo. 3-269756 (1991) transmits a personal identification number forverifying a user together with image data, if the personalidentification number is read on a communication network, there arises aproblem that others can pretend to be the user. Also, since thetechnique disclosed in Japanese Patent Application Laid-Open No.6-124178 (1994) transmits information necessary for decrypting imagedata together with the image data, if the information is read on acommunication network, there arises a problem that others can decryptthe image data.

DISCLOSURE OF THE INVENTION

The present invention has been made with the aim of solving the aboveproblems, and it is an object of the invention to provide an imagerecording system capable of preventing others from pretending to be auser by transmitting information for verifying the user to an imagerecording apparatus after digesting the information by a one-wayfunction, and causing the image recording apparatus to digest directlyreceived information and verify the user by collating the digestedinformation, and provide the image recording apparatus.

Further, it is another object of the invention to provide an imagerecording system capable of preventing decryption of image data byothers by transmitting information for verifying a user after encryptingimage data by using an encryption key, transmitting the informationafter digesting it by a one-way function, and causing the imagerecording apparatus to decrypt the image data by using directly receivedinformation as a decryption key, and provide the image recordingapparatus.

An image recording system according to the present invention is an imagerecording system comprising an image recording apparatus, and atransmitting apparatus, connected to the image recording apparatus, fortransmitting information to the image recording apparatus, andcharacterized in that the transmitting apparatus includes: firstconverting means for creating first converted information by convertingfirst information; and means for transmitting the created firstconverted information and an image record instruction to the imagerecording apparatus, and the image recording apparatus includes: meansfor receiving second information; second converting means for creatingsecond converted information by converting the received secondinformation; means for determining whether or not the received firstconverted information and the created second converted informationcorrespond to each other; and means for recording an image according tothe received image record instruction if a determination is made thatthe first converted information and the second converted informationproperly correspond to each other.

An image recoding system according to the present invention is an imagerecording system comprising an image recording apparatus, and atransmitting apparatus, connected to the image recording apparatus, fortransmitting information to the image recording apparatus, andcharacterized in that the transmitting apparatus includes: firstconverting means for creating first converted information by convertingfirst information; means for creating encrypted image data by encryptingimage data by using the first information as an encryption key; andmeans for transmitting the created first converted information andencrypted image data to the image recording apparatus, and the imagerecording apparatus includes: means for receiving second information;second converting means for creating second converted information byconverting the received second information; determining means fordetermining whether or not the received first converted information andthe created second converted information coincide; means for decryptingthe received encrypted image data by using the second information as adecryption key; and means for recording an image created based on thedecrypted image data if a determination is made that the first convertedinformation and the second converted information coincide.

An image recording system according to the present invention ischaracterized in that the first converting means and the secondconverting means digest information by using a one-way function.

An image recording apparatus according to the present invention is animage recording apparatus for recording an image according to an imagerecord instruction received from other apparatus, and characterized bycomprising: means for receiving an image record instruction and firstconverted information from other apparatus; means for receiving oneinformation; converting means for creating second converted informationby converting the received information; means for determining whether ornot the received first converted information and the created secondconverted information correspond to each other; and means for recordingan image according to the received image record instruction if adetermination is made that the first converted information and thesecond converted information properly correspond to each other.

An image recording apparatus according to the present invention is animage recording apparatus for recording an image created based on imagedata received from other apparatus, and characterized by comprising:means for receiving encrypted image data and first converted informationfrom other apparatus; receiving means for receiving one information;converting means for creating second converted information by convertingthe received information; determining means for determining whether ornot the received first converted information and the created secondconverted information coincide; means for decrypting the receivedencrypted image data by using the information received by the receivingmeans as a decryption key; and means for recording an image createdbased on the decrypted image data if the determining means determinesthat the first converted information and the second convertedinformation coincide.

An image recording apparatus according to the present invention ischaracterized in that the converting means digests information by usinga one-way function.

According to the present invention, in a system in which information forverifying a user is transmitted together with an image recordinstruction to the image recording apparatus from the transmittingapparatus, and the image recording apparatus records an image when itreceives corresponding information by operation of the user, thetransmitting apparatus transmits the first converted information createdby converting the first information for verifying the user, and theimage recording apparatus converts the second information received byoperation of the user into the second converted information, and recordsan image if the first converted information and the second convertedinformation properly correspond to each other.

According to the present invention, in a system in which information forverifying a user is transmitted together with image data to the imagerecording apparatus from the transmitting apparatus and the imagerecording apparatus records an image when it receives correspondinginformation by operation of the user, the transmitting apparatustransmits the first converted information created by converting thefirst information for verifying the user and encrypted image datacreated by encrypting image data by using the first information as anencryption key, and the image recording apparatus converts the secondinformation received by operation of the user into the second convertedinformation, decrypts the encrypted image data by using the secondinformation as a decryption key if the first converted information andthe second converted information coincide, and records an image.

According to the present invention, the first converted information andthe second converted information are created by digesting information byusing a one-way function.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a conceptual view showing an outline of the present invention;

FIG. 2 is a block diagram showing the structure of an image recordingsystem of the present invention and the internal structure of an imagerecording apparatus of the present invention;

FIG. 3 is a flowchart showing the processing step of transmitting animage record instruction from a transmitting apparatus to the imagerecording apparatus;

FIGS. 4A and 4B are schematic views showing an example of the outputscreen of the transmitting apparatus when transmitting an image recordinstruction;

FIG. 5 is a conceptual view showing an example of the storage contentsstored in a storing unit of the image recording apparatus;

FIG. 6 is a flowchart showing the processing step of recording an imageby the image recording apparatus;

FIG. 7 is a flowchart showing the processing step of recording an imageby the image recording apparatus; and

FIGS. 8A and 8B are schematic views showing an example of the outputscreen in an operation unit of the image recording apparatus whenrecording an image.

BEST MODE FOR CARRYING OUT THE INVENTION

The following description will specifically explain the presentinvention, based on the drawings illustrating an embodiment thereof.

FIG. 1 is a conceptual view showing an outline of the present invention.An image recording system of the present invention comprises an imagerecording apparatus 1 of the present invention that is a printingapparatus, and a transmitting apparatus 2 according to the presentinvention connected to the image recording apparatus 1. The transmittingapparatus 2 is composed of a computer such as a personal computer (PC),creates image data to be recorded as an image by the image recordingapparatus 1, encrypts the image data by using an authentication code,which is the first information according to the present invention andinputted by operation of the user or stored in advance, as an encryptionkey, and transmits the encrypted image data to the image recordingapparatus 1. The transmitting apparatus 2 digests the authenticationcode by using a one-way function such as a one-way hash function tocreate the first converted information, and transmits the firstconverted information to the image recording apparatus 1. The imagerecording apparatus 1 receives an authentication code that is the secondinformation according to the present invention by operation of the user,digests the received authentication code by using a one-way function tocreate the second converted information, and collates the created secondconverted information with the received first converted information toverify the user. When the second converted information and the firstconverted information coincide, it is verified that the user of thetransmitting apparatus 2 and the user operating the image recordingapparatus 1 are the same user, and then the image recording apparatus 1decrypts the received encrypted image data into image data by using thereceived authentication code as a decryption key, and creates andrecords an image based on the decrypted image data.

FIG. 2 is a block diagram showing the structure of an image recordingsystem of the present invention and the internal structure of the imagerecording apparatus of the present invention. The image recordingapparatus 1 comprises a control unit 11 composed of a CPU for performingoperations, a RAM for storing temporary information concerning theoperations, etc., and connected to a ROM 15 storing a control programfor controlling the image recording apparatus 1, and the control unit 11controls the image recording apparatus 1 entirely according to thecontrol program stored in the ROM 15. Moreover, a management unit 14that is a memory for storing management information indicting the statusof the image recording apparatus 1 is connected to the control unit 11,and the control unit 11 refers to the management information stored inthe management unit 14 and controls the image recording apparatus 1based on the referred management information. Further, an image readingunit 16 for scan-reading an image recorded on a sheet and creatingelectronic image data based on the read image, and an image forming unit17 for forming an image from the image data and outputting the formedimage by recording it on a recording sheet are connected to the controlunit 11, and the image recording apparatus 1 functions as a copyingmachine for copying an image read by the image reading unit 16. Inaddition, a storing unit 18 composed of a hard disk or a non-volatilememory is connected to the control unit 11, and the storing unit 18stores image data. Moreover, an operation unit 12 for receiving anoperation from the user is connected to the control unit 11, and theoperation unit 12 comprises display means such as a liquid crystal panelfor displaying information necessary for the operation, and input meanssuch as a touch panel or ten-key through which information such as acontrol command is inputted by operation of the user.

Further, a communication unit 13 connected to a communication network N,such as a LAN, is connected to the control unit 11, and thecommunication unit 13 exchanges information with an external apparatusthrough the communication network N. A plurality of transmittingapparatuses 2, 2, . . . are connected to the communication network N,the communication unit 13 receives image data transmitted from atransmitting apparatus 2 through the communication network N and storesthe received image data in the storing unit 18, the image forming unit17 can form an image from the image data and output the image, and theimage recording apparatus 1 functions as a printing apparatus. Inaddition, the image recording apparatus 1 can transmit the image datacreated by reading an image with the image reading unit 16 to thetransmitting apparatus 2 from the communication unit 13 through thecommunication network N, and functions as a scanning apparatus.Moreover, the communication unit 13 can perform facsimile communication,and functions as a facsimile machine for exchanging image data with anexternal facsimile machine by facsimile communication through anexternal communication network (not shown) connected to thecommunication network N.

The transmitting apparatus 2 comprises a CPU 21 for performingoperations, a RAM 22 for storing temporarily information created for theoperations, an external storage device 23 such as a CD-ROM drive, and aninternal storage device 24 such as a hard disk, and reads a computerprogram 30 from a recording medium 3 such as a CD-ROM in the externalstorage device 23, stores the read computer program 30 in the internalstorage device 24 and loads the computer program 30 into the RAM 22, andthe CPU 21 executes processes necessary for the transmitting apparatus2, based on the loaded computer program 30. Further, the transmittingapparatus 2 comprises a communication unit 27 connected to thecommunication network N, and transmits an image record instruction tothe image recording apparatus 1 through the communication network N. Inaddition, the transmitting apparatus 2 comprises an input unit 25 suchas a keyboard or a mouse, and an output unit 26 such as a liquid crystaldisplay or a CRT display, and is constructed to receive operations suchas an input of information from an operator.

The computer program 30 includes a one-way hash function for digestinginformation, and the ROM 15 of the image recording apparatus 1 stores asimilar one-way hash function.

FIG. 3 is a flowchart showing the processing step of transmitting animage record instruction from a transmitting apparatus 2 to the imagerecording apparatus 1, and FIGS. 4A and 4B are schematic views showingan example of an output screen of the transmitting apparatus 2 whentransmitting an image record instruction. On the screen of the outputunit 26 as shown in FIG. 4A, when a user selects an image recordingapparatus 1 that is a printing apparatus for use in recording an image,inputs a print range and the number of copies to be printed andspecifies OK, then the transmitting apparatus 2 receives an image recordinstruction, such as an instruction to record an image created by thetransmitting apparatus 2 that is a PC, at the input unit 25 (S101), andthe CPU 21 loads the computer program 30 into the RAM 22, follows theloaded computer program 30, outputs a job management screen as shown inFIG. 4B to the output unit 26, and outputs an instruction to input anauthentication code that is the first information according to thepresent invention for verifying the user (S102). On the job managementscreen as shown in FIG. 4B, it is possible to select an image recordingmethod from “Normal printing” in which the image data is transmitted andthe image is recorded as it is, “Hold after printing” in which the imagedata is held after recording the image, and “Hold without printing” inwhich the image data is held until an instruction is directly inputtedto the image recording apparatus 1, and when “Hold without printing” isspecified, the image recording system of the present invention performsthe processes according to the present invention. The CPU 21 monitorsreception of an authentication code at the input unit 25 given byinputting the user name, job name and authentication code and specifyingOK on the screen by the user as shown in FIG. 4B (S103), and if anauthentication code is not received because the user specifies Cancel onthe screen shown in FIG. 4B or other reason (S103: NO), then the CPU 21follows the computer program 30 loaded in the RAM 22, returns the screento be outputted to the output unit 26 to the screen shown in FIG. 4A,monitors reception of cancellation of image recording (S104), and ifcancellation is received at the input unit 25 (S104: YES), the CPU 21finishes the process, but if cancellation is not received (S104: NO),the CPU 21 returns the process to step S102 and outputs anauthentication code input instruction to the output unit 26.

If an authentication code is received in step S103 (S103: YES), then theCPU 21 follows the computer program 30 loaded in the RAM 22, encryptsthe image data of an image to be recorded by the image recordingapparatus 1 according to a common key method using the receivedauthentication code as an encryption key to create encrypted image data(S105), digests the authentication code by using a one-way hash functionto create the first converted information (S106), and transmits theencrypted image data and the first converted information from thecommunication unit 27 to the image recording apparatus 1 through thecommunication network N(S107).

The image recording apparatus 1 receives the encrypted image data andthe first converted information transmitted from the transmittingapparatus 2 through the communication network N at the communicationunit 13 (S108), the control unit 11 follows the control program storedin the ROM 15 and stores the received encrypted image data and firstconverted information in the storing unit 18 (S109), updates themanagement information stored in the management unit 14 by adding theinformation about the encrypted image data and first convertedinformation stored in the storing unit 18 (S110), and finishes theprocess. Note that, in the above-mentioned processes, the process ofreceiving the input of an authentication code is performed every time animage record instruction is received at the transmitting apparatus 2,but it may be possible to store an authentication code in thetransmitting apparatus 2 in advance and perform the encrypting anddigesting process by using the stored authentication code.

FIG. 5 is a conceptual view showing an example of the storage contentsstored in the storing unit 18 of the image recording apparatus 1.Information such as the user name, date and time, number of copies, andjob name are stored in association with encrypted image data, andfurther the first converted information is stored.

FIGS. 6 and 7 illustrate a flowchart showing the processing step ofrecording an image by the image recording apparatus 1, and FIGS. 8A and8B are schematic views showing an example of an output screen of theoperation unit 12 of the image recording apparatus 1 when recording animage. The image recording apparatus 1 receives an image recordinstruction by operation of the user through the operation unit 12(S201), and the control unit 11 follows a control program stored in theROM 15 and outputs a list of jobs of image recording corresponding tothe respective encrypted image data stored in the storing unit 18 to thedisplay means of the operation unit 12 as shown in FIG. 8A (S202). Thecontrol unit 11 monitors reception of job selection made by specifying ajob to record an image by the user on the screen as shown in FIG. 8A(S203), and if job selection is not received (S203: NO), the controlunit 11 finishes the process, but if job selection is received (S203:YES), the control unit 11 follows the control program stored in the ROM15 and outputs an authentication code input instruction to the displaymeans of the operation unit 12 (S204). FIG. 8B is an example of theoutput screen of the operation unit 12 for instructing to input anauthentication code, and if an authentication code consists of numerals,the user inputs the authentication code by operating the ten-key of theoperation unit 12, but if an authentication code includes characterssuch as alphabets, the user specifies a character input screen so thatthe screen for inputting characters is displayed to enable the input ofthe authentication code. According to the control program stored in theROM 15, the control unit 11 monitors reception of an authentication codeat the operation unit 12 (S205), and if an authentication code is notreceived (S205: NO), the control unit 11 monitors reception of a finishinstruction at the operation unit 12 (S206), and if a finish instructionis received (S206: YES), the control unit 11 finishes the process, butif a finish instruction is not received (S206: NO), the control unit 11returns the process to step S204 and outputs an authentication codeinput instruction to the operation unit 12.

In step S205, if an authentication code is received (S205: YES), thecontrol unit 11 follows the control program stored in the ROM 15,temporarily stores the received authentication code (S207), creates thesecond converted information by digesting the received authenticationcode by using a one-way hash function (S208), and determines whether ornot the first converted information stored in association with theselected job and the second converted information coincide (S209). Ifthe first converted information and the second converted information donot coincide (S209: NO), the control unit 11 follows the control programstored in the ROM 15, outputs an error indicating that theauthentication codes do not coincide to the display means of theoperation unit 12 (S210), monitors reception of a finish instruction atthe operation unit 12 (S211), and finishes the process if a finishinstruction is received (S211: YES), or returns the process to step S204and outputs an authentication code input instruction to the operationunit 12 if a finish instruction is not received (S211: NO). In stepS209, if a determination is made that the first converted informationand the second converted information coincide (S209: YES), the controlunit 11 follows the control program stored in the ROM 15, decrypts theencrypted image data into image data by using the temporarily storedauthentication code as a decryption key (S212), creates and records animage on a sheet according to the decrypted image data at the imageforming unit 17 (S213), and finishes the process.

As described in detail above, according to the present invention, in animage recording system in which an authentication code is transmittedtogether with image data to the image recording apparatus 1 from thetransmitting apparatus 2, and the image recording apparatus 1 stores thereceived image data and records an image when the same authenticationcode is inputted by operation of the user, the transmitting apparatus 2digests the authentication code by a one-way function and transmits itto the image recording apparatus 1, and similarly the image recordingapparatus 1 digests an authentication code received from the user by aone-way function and collates the digested authentication codes witheach other to determine whether or not they coincide. Since theinformation to be transmitted through the communication network N fromthe transmitting apparatus 2 to the image recording apparatus 1 isinformation created by digesting an authentication code by a one-wayfunction, even when it is read by others on the communication network,it is difficult for others to know the authentication code that shouldbe inputted to the image recording apparatus 1, and therefore it ispossible to prevent others pretending to be a user from causing theimage recording apparatus 1 to record an image and it is possible tomaintain the confidentiality of the information. Further, according tothe present invention, the transmitting apparatus 2 encrypts image databy using an authentication code as an encryption key and transmits thefirst converted information created by digesting the authentication codeand encrypted image data created by encrypting image data to the imagerecording apparatus 1, and the image recording apparatus 1 decrypts thereceived encrypted image data by using the received authentication codeas a decryption key, and therefore even when the information is read byothers on the communication network, it is difficult for others todecrypt the encrypted image data because it is difficult to know theauthentication code that is the decryption key from the first convertedinformation, and it is possible to maintain the confidentiality of theinformation.

Note that this embodiment illustrates a mode in which image data istransmitted from the transmitting apparatus 2, and the image recordingapparatus forms an image from the received image data and records it,but the present invention is not limited to this and may be performed ina mode in which the image recording apparatus 1 stores image data in thestoring unit 18, and an image record instruction for instructing tocreate and record an image based on image data stored in the storingunit 18 is transmitted from the transmitting apparatus 2 to the imagerecording apparatus 1. In this case, it is not necessarily to determinewhether or not the first converted information and the second convertedinformation coincide, and it may be possible to perform a mode using theprocess of determining whether or not they have a predeterminedcorresponding relationship. In this case, it is also possible tomaintain the confidentiality of information by transmitting anauthentication code digested by using the present invention andverifying the user.

INDUSTRIAL APPLICABILITY

As described in detail above, according to the present invention, thetransmitting apparatus transmits the first converted information createdby converting the first information for verifying a user, the imagerecording apparatus converts the second information received from a userinto the second converted information, and records an image if the firstconverted information and the second converted information properlycorrespond to each other, and thus it is possible to prevent others fromacquiring the information and pretending to be the user, and it ispossible to maintain the confidentiality of information.

Moreover, according to the present invention, the transmitting apparatustransmits the first converted information created by converting thefirst information for verifying a user and encrypted image data createdby encrypting image data by using the first information as an encryptionkey, and the image recording apparatus converts the second informationreceived from a user into the second converted information, decrypts theencrypted image data by using the second information as a decryption keyif the first converted information and the second converted informationcoincide, and records an image, and therefore even when others haveacquired the first converted information and encrypted image data, it ispossible to maintain the confidentiality of information because it isdifficult to decrypt the encrypted image data.

Further, according to the present invention, since the first convertedinformation and the second converted information are created byconverting information by using a one-way function, it is difficult forothers to know the information before converted, and it is difficult forothers to know the contents of the image by using the information, andthus the present invention has advantageous effects and can maintain theconfidentiality of information.

1-6. (canceled)
 7. An image recording system comprising: an imagerecording apparatus; and a transmitting apparatus, connected to saidimage recording apparatus, for transmitting information to said imagerecording apparatus, wherein said transmitting apparatus includes acontroller capable of performing operations of: creating first convertedinformation by converting first information; and transmitting thecreated first converted information and an image record instruction tosaid image recording apparatus, and said image recording apparatusincludes: a receiving unit for receiving second information; acontroller capable of performing operations of: creating secondconverted information by converting the received second information; anddetermining whether or not the received first converted information andthe created second converted information correspond to each other; andan image forming unit for recording an image according to the receivedimage record instruction if a determination is made that the firstconverted information and the second converted information properlycorrespond to each other.
 8. The image recording system according toclaim 7, wherein said controller of said transmitting apparatus and saidcontroller of said image recording apparatus digest information by usinga one-way function.
 9. An image recording system comprising: an imagerecording apparatus; and a transmitting apparatus, connected to saidimage recording apparatus, for transmitting information to said imagerecording apparatus, wherein said transmitting apparatus includes: acontroller capable of performing operations of: creating first convertedinformation by converting first information; and creating encryptedimage data by encrypting image data by using the first information as anencryption key; and a communication unit for transmitting the createdfirst converted information and encrypted image data to said imagerecording apparatus, and said image recording apparatus includes: areceiving unit for receiving second information; a controller capable ofperforming operations of: creating second converted information byconverting the received second information; determining whether or notthe received first converted information and the created secondconverted information coincide; and decrypting the received encryptedimage data by using the second information as a decryption key; and animage forming unit for recording an image created based on the decryptedimage data if a determination is made that the first convertedinformation and the second converted information coincide.
 10. The imagerecording system according to claim 9, wherein said controller of saidtransmitting apparatus and said controller of said image recordingapparatus digest information by using a one-way function.
 11. An imagerecording apparatus for recording an image according to an image recordinstruction received from other apparatus, comprising: a communicationunit for receiving an image record instruction and first convertedinformation from other apparatus; a receiving unit for receiving oneinformation; a controller capable of performing operations of: creatingsecond converted information by converting the received information; anddetermining whether or not the received first converted information andthe created second converted information correspond to each other; andan image forming unit for recording an image according to the receivedimage record instruction if a determination is made that the firstconverted information and the second converted information properlycorrespond to each other.
 12. The image recording apparatus according toclaim 11, wherein said controller digests information by using a one-wayfunction.
 13. An image recording apparatus for recording an imagecreated based on image data received from other apparatus, comprising: acommunication unit for receiving encrypted image data and firstconverted information from other apparatus; a receiving unit forreceiving one information; a controller capable of performing operationsof: creating second converted information by converting the receivedinformation; determining whether or not the received first convertedinformation and the created second converted information coincide; anddecrypting the received encrypted image data by using the informationreceived by the receiving unit as a decryption key; and an image formingunit for recording an image created based on the decrypted image data ifa determination is made that the first converted information and thesecond converted information coincide.
 14. The image recording apparatusaccording to claim 13, wherein said controller digests information byusing a one-way function.
 15. An image recording system comprising: animage recording apparatus; and a transmitting apparatus, connected tosaid image recording apparatus, for transmitting information to saidimage recording apparatus, wherein said transmitting apparatus includes:first converting means for creating first converted information byconverting first information; and means for transmitting the createdfirst converted information and an image record instruction to saidimage recording apparatus, and said image recording apparatus includes:means for receiving second information; second converting means forcreating second converted information by converting the received secondinformation; means for determining whether or not the received firstconverted information and the created second converted informationcorrespond to each other; and means for recording an image according tothe received image record instruction if a determination is made thatthe first converted information and the second converted informationproperly correspond to each other.
 16. The image recording systemaccording to claim 15, wherein said first converting means and saidsecond converting means digest information by using a one-way function.17. An image recording system comprising: an image recording apparatus;and a transmitting apparatus, connected to said image recordingapparatus, for transmitting information to said image recordingapparatus, wherein said transmitting apparatus includes: firstconverting means for creating first converted information by convertingfirst information; means for creating encrypted image data by encryptingimage data by using the first information as an encryption key; andmeans for transmitting the created first converted information andencrypted image data to said image recording apparatus, and said imagerecording apparatus includes: means for receiving second information;second converting means for creating second converted information byconverting the received second information; determining means fordetermining whether or not the received first converted information andthe created second converted information coincide; means for decryptingthe received encrypted image data by using the second information as adecryption key; and means for recording an image created based on thedecrypted image data if said determining means determines that the firstconverted information and the second converted information coincide. 18.The image recording system according to claim 17, wherein said firstconverting means and said second converting means digest information byusing a one-way function.
 19. An image recording apparatus for recordingan image according to an image record instruction received from otherapparatus, comprising: means for receiving an image record instructionand first converted information from other apparatus; means forreceiving one information; converting means for creating secondconverted information by converting the received information; means fordetermining whether or not the received first converted information andthe created second converted information correspond to each other; andmeans for recording an image according to the received image recordinstruction if a determination is made that the first convertedinformation and the second converted information properly correspond toeach other.
 20. The image recording apparatus according to claim 19,wherein said converting means digests information by using a one-wayfunction.
 21. An image recording apparatus for recording an imagecreated based on image data received from other apparatus, comprising:means for receiving encrypted image data and first converted informationfrom other apparatus; receiving means for receiving one information;converting means for creating second converted information by convertingthe received information; determining means for determining whether ornot the received first converted information and the created secondconverted information coincide; means for decrypting the receivedencrypted image data by using the information received by said receivingmeans as a decryption key; and means for recording an image createdbased on the decrypted image data if said determining means determinesthat the first converted information and the second convertedinformation coincide.
 22. The image recording apparatus according toclaim 21, wherein said converting means digests information by using aone-way function.